"In the spring, I went to Los Angeles, and met and started to date a wonderful woman named Olivia – Olivia Munn," Mulaney, 39, said Tuesday night on "Late Night with Seth Meyers." "And we're having a baby together. … I'm going to be a dad. We're both really, really happy."
This will be the first child for Mulaney and Munn, 41. The actress was previously in a relationship with Green Bay Packers quarterback Aaron Rodgers before the couple split in 2017.
Mulaney has worked through a "challenging time," he told Meyers, a longtime friend. Reports emerged in May that Mulaney and his wife Anna Marie Tendler were divorcing after six years of marriage. The split came after the comedian, who has been open about past struggles with alcoholism and drug addiction, checked in to rehab in September. He left rehab the next month and moved out of the home he shared with his "ex-wife" shortly before hosting the Halloween episode of "Saturday Night Live," Mulaney recapped.
"I did relapse back onto drugs after that," he told Meyers. "Then I continued using drugs, you and some other friends staged an intervention, as you recall."
Meyers' recollection of the intervention was "awful," he said. "You do those things because you're really worried about your friend."
Mulaney joked it was a "'We Are The World' of alternative comedians over the age of 40," including "SNL" alum Fred Armisen, but was disappointed that none of them did bits.
"I didn't want an intervention," Mulaney said. "At that moment in time, I wanted to continue using drugs. Sitting here tonight, I'm so grateful to you and to everyone there for saving my life. That night, I was not grateful."
He added: "You guys saved me from drugs and Olivia and this baby have helped save me from myself and this early journey out of recovery. I don't have a joke for that. I'm really grateful to you, buddy."
Mulaney returned to rehab and stayed for two months. He got out in February and stayed in sober living for a month and a half before heading to Los Angeles, where he re-met Munn – the two met for the first time at Meyers' wedding to Alexi Ashe in 2013 ("so it's nice that something good came out of the wedding," Mulaney joked).
"She got to date me right out of recovery, which is what they call a reverse catch," Mulaney said of Munn. "But it is a very, very lucky thing to have met this woman. … I got into this relationship that's been really beautiful and with someone incredible who has dealt with the non-coked up version of me. That's been very incredible and she kind of held my hand through that hell."
Mulaney has previously opened up about past substance abuse – according to his 2019 profile in Esquire, he starting drinking alcohol at 13.
“I drank for attention,” he told the magazine. “I was really outgoing, and then at twelve, I wasn’t. I didn’t know how to act. And then I was drinking, and I was hilarious again.”
He added: "I never liked smoking pot. Then I tried cocaine, and I loved it. I wasn’t a good athlete, so maybe it was some young male thing of 'This is the physical feat I can do. Three Vicodin and a tequila and I’m still standing. Who’s the athlete now?'"
Mulaney added that he quit using drugs and alcohol in 2005 when he was 23, without using a recovery program.
"I went on a bender that weekend that was just, like, fading in and out of a movie," he said. "I was like, 'You’re (expletive) out of control.' And I thought to myself, 'I don’t like this guy anymore. I’m not rooting for him.' "
Mulaney has also joked about his past issues with alcohol in stand-up routines. He is currently touring with a new stand-up show, titled "John Mulaney: From Scratch."
Contributing: Charles Trepany and Sara M. Moniuszko
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This article originally appeared on USA TODAY: John Mulaney confirms Olivia Munn is pregnant, talks rehab, divorce